Electrical circuit breaker



May 23, 19.39- o. K. BEcKLER 2,159,368

ELECTRICAL CIRCUIT BREAKER l @wr/K 19H/mae May 23, 1939- o. K. BECKLER 2,159,368

ELECTRICAL CIRCUIT BREAKER `F'iled Sept. 2, 1936 2 Sheets-Sheet 2 Patented May 23, 1939 UNITED STATES PATENT OFFICE ELECTRICAL CIRCUIT BREAKER Tex.

` Application September 2, 1936, Serial No. 99,071

13 Claims.

This invention relates to new and useful improvements in electrical circuitI breakers.

One object of the invention is to provide an improved electrical circuit breaker which is particularly adapted for use in the usual fuse box,

being substituted for the usual plug-type fuse.

An important object of the invention is to provide an improved electrical device arranged to be inserted in the usual electrical receptacle, and

m which will act as a thermostatic cutout or circuit breaker and which will not burn out or be destroyed When operated but may be restored to circuit closing position and repeatedly re-used.

Another object of the invention is to provide a plug-type circuit breaker which is 'arranged to produce a snap action in breaking the circuit and which requires manual resetting in order to again close the circuit; the structurebeing such that the circuit is broken during the re-setting operation, whereby danger of spark, as well as any danger of electrical shock to the operator is eliminated.

A further object of the invention is to provide an improved plug-type circuit breaker employing a resilient member sensitive to predetermined electrical variations and normallyrestrained to complete the electric circuit, but arranged to disengage itself and open said circuit upon predetermined circuit variations, there being means independent of the member for breaking the circuit while the member is being returned to its engaged position, whereby the circuit is not closed until the re-setting operation is complete.

A still further object of the invention is to provide an improved circuit breaker for use in an ordinary fuse box which is constructed of a minimum number of working parts and which has substantially the same size and shape as the usual plug-type fuse.

A construction designed to carry out the invention will be hereinafter described, together with other vfeatures of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in which an example of the invention is shown, and wherein: j

Figure 1i is a side elevation of a. circuit breaker, constructed in accordance with the invention,

Figure 2 is -a transverse, vertical sectional view, showing the'device in its circuit closing position,

Figure 3 is a similar view showing the same disengagedyf Figure '4 -isr' anl enlarged transverse sectional view'with the housing omittedv viewing the parts (Cl. 20o-116) from the side opposite to Figure 2, and showing the circuit closing position,

Figure 5 is a similar View, with the circuit broken,

Figure 6 is a similar view, showing the position of the part .during the re-setting operation,

Figure 7 is an enlarged horizontal, cross-sectional view, taken on the line l-'I of Figure 2,

Figure 8 is a transverse, vertical sectional view, taken on the line 8--8 of Figure 4,

Figure 9 is a transverse, vertical sectional view, taken on the line 9 9 of Figure 4,

Figure l0 is a transverse, vertical sectional view, taken on the line II'I--I 0 of Figure 5,

Figure 11 is a transverse, vertical sectional view, taken on the line I I-II of Figure 6,

Figure 12 is a. transverse, vertical sectional view, taken on the line I2-I2 of Figure 6,

Figure 13 is a horizontal cross-sectional view, taken on the line I3-I3 of Figure 4,

Figure 14 is an isometric view of one side of the insulating block, and

Figure 15 is an isometric view of the other side of the block.

In the drawings, the numeral I 0 designates a hollow, cylindrical shell or housing which is constructed of glass, or other electrical non-conducting material. One end of the housing is open while the opposite end is closed by an end wall I-I, which wall is formed with an axial opening I2 therein. The end wall is preferably made integral with the housing or shell and an annular outwardly extending flange I3 is formed at this closed end of the shell. The shell or housing is substantially of the same size and shape as the ordinary'plug-type fuse, whereby it may be inserted in the usual electrical receptacle which receives such fuse.

An insulating block I4, constructed of a suitable electrical non-conducting material is arranged to be inserted into the open end of the shell or housing l0. The block is substantially rectangular in cross-section, (Figure 13) having a length less than the diameter of the shell, and has a circular head or disk I5, constructed of the same material, integral with its outer end. The diameter of the head is substantially the same as that of the shell, and since the length of the block is less than the diameter of the shell, a peripheral flange I5' `is formed around the block. When said block is inserted within the shell, the flange I5 engages the edge of the shell (Figures 2 -and 3) and an annular metallic collar I6 which is threaded on'the shell is provided with an inturned annular lip I1 which engages the marginal portion of said head to fasten the head and block to the shell. The threads of the collar are formed by a pressing operation, whereby said collar is provided with external, as well as internal threads. These external threads may be utilized for screwing the shell into the usual electrical receptacle which is provided for the reception of plug-type fuses. it is noted that the collar I6 may be riveted or otherwise secured on the shell and the invention is not to be limited to threading said collar thereon, although this latter method makes for easy disassembling of the device.

For conducting electrical current through the circuit breaker, the block I4 is provided with a laterally extending, .narrow contact bar I8 at side thereof (Figures 4, 6 and 9), which bar is located near the upper end of the block. One end of the bar is disposed near the central portion of the side of said block, while the opposite end is curved around one corner of the block so as to overlie the end thereof (Figure 13). A vertical bar I8 preferably a continuation of the bar I 8 lies contiguous to this end of the block and has its upper end integral with or otherwise connected With the contact bar. The bar I8 extends downwardly along the end wall of the block and passes through an opening I9 formed in the head or disk I5 (Figure 2). After passing through the head, the bar is bent to lie contiguous to the head to form an elongate contact 20.

With this arrangement, it will be obvious that when the shell or housing is inserted into the usual electrical receptacle, the elongate contact 20 will engage the usual axial contact (not shown) which is provided in the receptacle, whereby electrical current flows through the bar I8 and to the contact bar I8. It is noted that the bar I8' and contact 28 need not be integral with each other or with the contact I8, but it is preferable to make them so.

An L-shaped contact member 2| is set within the block I4 on the side opposite the bar I8 (Figures 2, 3, 9 and 10). The horizontal portion 2 of this member is located directly opposite the bar I8 and covers substantially one half of the side of said block. The laterally extending portion 22 of said member covers the lower portion of the other half of said block whereby the upper portion of the block above the portion 22 is exposed (Figures 2 and 3). 'Ihe extreme upper end of the vertical portion 2|' is formed with an outwardly curved lip 23 (Figures 9 and 12).

For electrically connecting the contact bar I8 on one side of the block with the contact member 2| on the opposite side, a metallic U-shaped connecting member or yoke 24 is positioned to span the block (Figures 2, 3 and 9). One of the yoke arms is offset inwardly to provide an offset foot 25 which is adapted to engage the contact bar I8. The opposite yoke ann is formed with a latch 26, which is arranged to engage the lip 23 on the portion 2| of the member 2|. The yoke is normally held in position with its arms engaging the bar I8 and member 2| by a coiled spring 2l conned between the yoke and block (Figure 9). The spring surrounds a guide pin 28 which is slidable in a vertical opening 29 in the block, and this spring exerts its tension to normally hold the yoke in a raised position with the latch 26 engaging the lip 23 and the offset foot 25 engaging the bar I8.

From the above, it will be seen that the electrical current flowing through the bar I8 will pass through the metallic yoke 24 and to the contact member 2 I. When the yoke is depressed or moved downwardly against tension of the coiled spring 2l, it will be obvious that the offset foot 25 will ride oiT of the bar i8 and onto the exposed portion of the block therebeneath (Figure l2). Since the block is constructed of insulating material, this downward movement of the yoke will break the electrical circuit between the bar I8 and member 2l. Of course, as soon as the yoke is released, the spring 2l will immediately raise Sai-d yoke to 1re-engage the foot 25 with the bar i8 to again close the circuit.

A laterally extending contact plate 38 is mounted within the block I4 on the same side as is the contact bar I8 (Figures 4, 5, 8 and 10). The plate is located directly opposite the laterally ex tending portion 22 of the member 2| and is disposed at the lower end of the block. It is noted that there is no connection between this plate and the bar I8. The upper end of the plate is bent outwardly to form a lip or flange 3| which is located below an overhanging shoulder 32 provided on the block. The shoulder is formed by inclining the side of the block above the plate outwardly at a slight angle from the vertical, as is clearly shown in Figures 8, 10 and l1.

The lower end of the plate is preferably made integral with a iiat connecting bar 33 which overlies the ange I5 of the head. This bar extends outwardly to the margin of the head and is then bent upwardly to provide a vertical contact bar 34. When the block is in position within the housing or shell, the contact bar 34 engages within a vertical recess 35 (Figure 7) provided in the outer surface of the shell, whereby the outer face of said bar is substantially flush with the surface of said shell. Thus, when the threaded collar I 6 is in position on the shell, said collar engages the bar 34 to make electrical contact therewith.

For electrically connecting the plate 30 with the L-shaped contact member 2| on the opposite side of the block, a second U-shaped member or yoke'36 is provided. This yoke is constructed of thermostatic or bi-metallic material, whereby it will undergo expansion or distortion under excessive heat. This metal of which the yoke is constructed of course, has an inherent resiliency or springiness and thus when said yoke spans the block I4, the arms of said yoke snugly engage the opposite sides of the block (Figure 8).

One of the yoke arms 3I is adapted to engage the lateral portion 22 of the L-shaped contact member, while the opposite yoke arm 38 has its lower end bent inwardly to form a latch 39 for engaging the lip or flange 3| of the Contact plate 30. A coiled spring 40 surrounds a guide pin 4I carried by the yoke and is conned between the yoke and block. The guide pin is slidable in a i vertical opening 42 in the block, and the spring is, at all times, exerting its pressure to move the yoke upwardly. However, under normal conditions the yoke is depressed, as shown in Figure 8, with its arms closing the electrical circuit between thev member 2| and plate 30, For depressing the yokes 24 and 38, a button 43 extends through the opening I2 in the end wall of the shell or housing. This buttonis constructed of insulating material and has an annular ilange 44 at its lower end. The ilange overlies both yokes and it is obvious that by depressing the button either one or both of the yokes may be depressed.

In operation, the housing or shell is inserted in the usual electrical receptacle (not shown) and the yoke 24 is raised and engaging the contact bar I8 and member 2| (Figure 9) while the yoke 36 is depressed and engaging the member 2| and plate 30. With' the yokes in this position, the electrical current will flow from the axial contact of the usual receptacle (not shown) to the elongate contact bar 20, through bar I8, yoke 24, member 2l, yoke 36, plate 30', bar 34 and nally to the metallic collar I6 and to the other side of the circuit in the receptacle to complete the eleotrical circuit. With the .parts in this position, the circuit is closed .as the current is flowing through both yokes 24- and 36 and their respective contacts. The bi-metallic yoke 36 is constructed so as to carry-a predetermined flow of current and so long as normal conditions prevail, the parts remain in this position.

In the event that there occurs anoverload or short circuit in the current flowing through the device, the bi-metallic yoke 36 immediately becomes heated. This heating of said yoke causes an expansion of the same and such expansion disengages the latch 39 from the lip 3l of the plate 30, permitting the coiled spring 40 to immediately raise the yoke. As the yoke moves upn wardly, the arms thereof ride onto the exposed surface of 'the block and disengage the Contact member 2I and plate 3U, whereby the circuit be= tween the contact bar 20 and contact bar 34 is broken. As said yoke moves upwardly, it raises the button 43 from the position shown in Figure 2 to that shown in Figure 3, to advise the ohserver that the circuit through the device is broken. It is noted that upward movement oi said yokeis limited by the engagement of the flange 44 with the inside of the end wall of the shell. Thus, as'shown in Figure l0, the circuit is open since the current cannot iiow through the yoke 36 as said yoke has its ends engaging the insulating block.

As soonas the circuit is broken, the yoke 36 cools and the arms thereof immediately return to their normal position, snugly engaging the sides of the block (Figure 10). It is pointed out that through the use of the latch 36 and lip 3 I, as well as the spring 40, a snap action in disengaging the yoke is obtained. This snap action is advantageous as it reduces danger of arcing to a minimum; The yoke, after moving to its raised position will remain so until manually re-set.

When it is desired to re-set the yoke 36 to again close the circuit it is only necessary to depress the button 43. The ilange 44 of this button engages the upper end of the yoke and moves the same downwardly under tension of the spring 40. It is noted that during the operation of the yoke 36, the yoke 24 has maintained its same raised position. Since the flange 44 of the button overlics both yokes, depression of said button in re-setting the yoke 36 will cause simultaneous depression of the yoke 24. Depression of this latter yoke will cause the offset root 25 thereof, to ride off ofthe lateral contact bar I8, whereby electrical connection between this bar and the contact member 2l is broken. Therefore, so long as the yoke 24 is depressed no currentfcan pass through thisyoke.

The bar I8 is of such size and so positioned with relation to the contact plate 3U that upon depressionk of both yokes 24 and 36, the yoke 24 breaks electrical connection between the bar I8 and member 2I before the yoke 36 is re-engaged with the plate 30 and member 2 I. In other Words, upon initial depression, the foot 25 rides off the contact I8 before the latch 39 engages the lip 3l of the plate 3D. Therefore, at the time the yoke 36 is re-set, no current is flowing through the device because the current is broken between the bar I8 and member 2I. The circuit is therefore open during the resetting operation since one end of the yoke 24 is riding on the surface of the insulating block. Thus, all danger of arcing as the bi-metallic yoke aproaches the plate 30 and member 2| is eliminated. This is an important feature of the invention.

After the yoke 36 has been re-set, the button is released and the coiled spring 21 beneath the yoke 24 immediately raises said yoke to its original position (Figure 9) to re-engage the yoke arms with the bar I8 and memebr 2i, whereby the circuit through the device is again complete. With this arrangement, it is obvious that the bi-metallic yoke 36 is re-set only when the circuit is broken and therefore, damage to said member because of arcing is obviated. Also danger of any shock to the operator is eliminated. because the electrical circuit through the device is not completed until the button is released.

What I claim and desire to secure by Letters Patent, is:

l. A circuit breaker for engagement within an electrical receptacle including, an insulating y block, electrical contacts mounted on said block,

a bi-metallic element normally engaging the contacts to electrically connect the same, means for effecting a disengagement of said element from said contacts when said element is heated due to overload or short circuit, means for re-engaging said element, and means mounted on the block and connected in the circuit for breaking the electrical circuit to the contacts during the re-setting of said element.

2. A circuit breaker including, a shell adapted to be inserted into an ordinary electrical receptacle, an insulating block mounted within said. shell, electrical contacts mounted on said block, a bi-nietallic element normally engaging the con-1 tacts to electrically connect the same, means lor effecting a disengagement of said element from said contacts when said element is heated due to overload or short circuit, means for re-engaging said element, and means mounted on the block and connected in the circuit for breaking the electrical circuit to the contacts during the re-setting of said element.

3. A circuit breaker including, an insulating v block, a pair of electrical contacts one on each side of said block, a loi-metallic yoke element spanning the block and having its arms engaging said contacts to electrically connect the same, means for normally holding said yoke arms in engagement with the contacts, means for effecting a disengagement of the yoke arms when said yoke becomes heated due to an overload or short circuit, means for re-setting the yoke after such disengagement, and means for cutting oi the electrical current to the contacts during the resetting operation. v

4. A circuit breaker including, a shell adapted to be inserted into an ordinary electrical receptacle, an insulating block mounted within said shell, a pair of electrical contacts one on each side of said block, a bif-metallic yoke element spanning the block and having its arms engaging said contacts to electrically `connect the same, means for normally holding said yoke arms in engagement with the contacts, means for effecting a disengagement of the yoke arms when said yoke becomes heated due to an overload or short circuit, means for re-setting the yoke after such disengagement, and means for cutting off the electrical current to the contacts during the re-setting operation.

5. A circuit breaker including, an insulating block, electrical contacts mounted on said block,

va loi-metallic element normally engaging the contacts to electrically connect the same, means for effecting a disengagement of said element from said contacts when said -element is heated due to overload or short circuit, means for re-engaging said element, means movable with relation to the block for breaking the electrical circuit to the contacts during the re-setting of said element, and manually operable means for 'simultaneously operating the last named means and the re-engaging means for said element.

6. A circuit breaker including, an insulating block, a pair of electrical contacts one on each side of said block, a bi-metallic yoke element spanning the block and having its arms engaging said contacts to electrically connect the same, means for normally holding said yoke arms in engagement with the contacts, means for effecting a disengagement of the yoke arms when said yoke becomes heated due to an overload or short circuit, means for re-setting the yoke after such disengagement, means for cutting off the electrical current to the contacts during the resetting operation, and manually operable means for simultaneously operating the last named means and the re-engaging means for said element.

7. A circuit breaker including, a shell adapted to be inserted into an ordinary electrical receptacle, an insulating block mounted within said shell, electrical contacts mounted on said block, a bi-metallic element normally engaging the contacts to electrically connect the same, means for effecting a disengagement of said element from said contacts when said element is heated due to overload or short circuit, means movable with relation to the block for re-engaging said element, means for breaking the electrical circuit to the contacts during the re-setting of said element, and manually operable means for simultaneously operating the last named means and the re-engaging means for said element.

8, A circuit breaker including, an insulating block, a contact bar mounted at one side of the block and connected to one side of an electrical circuit, a contact member on the opposite side of said block, movable means for electrically connecting the bar and member, a contact plate on said block on the same side as the bar but having no electrical connection therewith, said plate being connected with the other side of the circuit, a movable bi-metallic element adapted to connect the plate with said contact member, means for effecting a disengagementof the element with the-plate and member to break the circuit therebetween when the element is heated due to overload or short circuit, means for resetting said element to again engage the plate and member after disengagement, and means for moving the means connecting the contact bar and contact member to electrically disconnect the same during the re-setting whereby the electrical circuit is broken during the re-setting operation.

9. A circuit breaker including, an insulating block, a contact bar mounted at one side of the block and connected to one side of an electrical circuit, a contact member on the opposite side of said block, movable means for electrically connecting the bar and member, a contact plate on said block on the same side as the bar but having no electrical connection therewith, said plate being connected with the other side of the circuit, a movable bi-metallic element normally manually operated means for re-engaging the element with the plate and contact member and for simultaneously moving the means connecting the contact bar and contact member to electrically disconnect said plate and member, lwhereby the'electrical circuit is broken during the re-setting.

l0. A circuit breaker including, a shell adapted to be inserted within an ordinary electrical receptacle, an insulating block mounted within said shell, a contact bar mounted at one side of the block and connected to one side of an electrical circuit, a contact member on the opposite side of said block, movable means for electrically connecting the bar and member, a Contact plate on said block on the same side as the bar but having no electrical connection therewith, said plate being connected with the other side of the circuit, a movable bi-metallic element normally connecting the plate with said contact member, means for effecting a disengagement of ythe element with the plate and member to break the circuit therebetween when the element is heated due to overload or short circuit, means for re-setting said element to again engage the plate and member after dis-l engagement, and means for moving lthe means connecting the contact bar and contact member to electrically disconnect the same during the re-setting whereby the electrical circuit is broken during the re-setting opera-tion.

11. A circuit breaker including, a shell adapted to be inserted within `an ordinary electrical receptacle, an insulating block mounted within said shell, a contact bar mounted at one side of the block and connected to one side of an electrical circuit, a contact member on the op-I posite side of said block, movable means for electrically connecting the bar and member, a contact plate on said block on the same side as the bar but having no electrical connection therewith, said plate being connected with the other side of the circuit, a movable bi-metallic element normally connecting the plate with said contact member, means for effecting adisengagement of the element with the plate and member to break the circuit therebetween when the element is heated due to overload of short circuit, and a single manually operated means for re-engaging the element with the plate and Contact member and for simultaneously moving the means connecting the contact bar and contact member to electrically disconnect said plate and member, whereby the electrical circuit is broken during the re-setting.

12. A circuit breaker including, an insulating block, a contact bar mounted at one side of the block and connected to one side of an electrical circuit, a contact member on the opposite side of said block, movable means for electrically connecting the bar and member, a con` tact plate on said block on the same side as the bar but having no electrical connection therewith, said plate being connected with the other side of the circuit. a movable bi-metallic yoke spanning the block and normally connecting the plate with said contact member, means for effecting a disengagement of the yoke with the plate and member to break the circuit therebetween when the yoke is heated due to overload or short circuit, means for re-setting said yoke to again engage the plate and member after disengagement, and means for moving the means connecting the con-tact bar and contact member to electrically disconnect the same during the re-setting whereby the electrical circuit is broken during the re-setting operation.

13. A circuit breaker including, an insulating block, a contact bar mounted at one side of the block and connected to one side of an electrical circuit, a contact member on the opposite side of said block, a yoke for electrically connecting the bar and member, a contact plate on said block on the same side as the bar but having no electrical connection therewith, said plate being connected with the other side of the circuit, a movable bi-metallic element normally connecting the plate with said contact member, means for eiecting a disengagement of the element with the plate and member to break the circuit therebetween when the element is heated due to overload or short circuit, means for re-setting said element to again engage the plate and member after disengagement, and means for moving the yoke connecting the contact bar and contact member to electrically disconnect the same during the re-setting whereby the electrical circuit 15 

